1. Field of the Invention
The present invention relates generally to a water filtration system for residential homes. More particularly, the water filtration system comprises one or more units of filtering U-shaped elements. Each filter element contains a three-layer bed of anthracite, sand and anthracite in particulate form held by end screens for removing iron and manganese contaminants. Also, pressure gauges, an alarm and a clarity analyzer containing a photocell are included in the system for monitoring and control. A backwashing procedure provides effective cleansing and regeneration of the water filtration system periodically. The filtration system can be housed in an insulated case with a lid on top and installed either in the ground, above the ground or in a basement.
2. Description of the Related Art
A common problem with household water is the excessive iron and manganese content which causes an objectional taste, a discoloration of the water, and accretion in the plumbing and washed clothes. The excessive contamination cannot always be eliminated by the local public water system. Therefore, pressure loss in house plumbing and outside pipes such as for repairs can cause the accreted contaminants to release and enter the water supply. There is, therefore, a need for an affordable, low-maintenance water filtration system for a dwelling. The design of the present invention includes screens which eliminates the loss of filter media during use and backwashing. It is known to reduce the chlorine taste of drinking water from a kitchen faucet by utilizing small portable activated charcoal units, but these units are inadequate to handle the incoming water supply of a dwelling.
The related art of interest describes various water filtration systems. The related art will be discussed in the order of perceived relevance to the present invention.
U.S. Pat. No. 3,497,068 issued on Feb. 24, 1970, to A. Adler Hirsch describes blended granular beds for water and wastewater filters. During the 1930's, dual bed filters containing an anthracite layer (1 mm. particles) on top of a sand layer (0.5 mm. particles) were used but discounted as not performing throughout the depth of the filter as a continuous unit. This fact was to be shown by a backwash catchment curve plotted in a FIG. 10 not present in the patent. Subsequently, a third finer and heavier layer of magnesite or garnet was added under the sand layer. This modification was considered disadvantageous as having a limited filter run and being less economical. Therefore, Hirsch shows the blending of fine and coarse granular material before placement and laid in shallow laminae in a downflow filter so that the average grain and pore size varies continuously and decreases with depth. The Hirsch filter is distinguishable for a large installation requiring a concrete filter box containing a specific blended filter bed over a gravel layer and an underdrain with downflow only of the unfiltered water.
U.S. Pat. No. 4,260,426 issued on April 7, to Daniel H. Werfelman describes a cylindrical deep bed filter for filtering food processing liquids. The tank (8 ft. high, 8 ft. diameter) has an inlet pipe on top and the outlet pipe at the bottom. A top screen, an intermediate movable (upward) media separator and a false bottom screen are provided and have the dimensions of #8 mesh, 0.032 in. square openings, and 8 ft. in diameter. The media separator separates a layer 2 ft. deep of #2 size anthracite from a packed bed of #50 size sand 4 ft. deep. During backwashing with air, caustic at pH 14, and air, the sand bed expands to elevate the movable media separator held by guides. The effluent Ph is maintained below 3 to prevent solubilization of the fats, oils and grease. The filter apparatus is distinguishable for its cylindrical, non-U-shaped structure and its essential movable intermediate screen required to separate the filter media.
U.S. Pat. No. 4,197,205 issued on Apr. 8, 1980, to Gene Hirs describes a vertical deep bed filter having multiple distinct layers starting from the bottom of sand, anthracite, nut or fruit shells, and a granular material comprising hydrophilic, hollow (spherical, cylindrical or frustro-conical) silica beads dispersed in a matrix of cured cement. The deep bed layers must increase in density and decrease in size from top to bottom. The filter bed is distinguishable for its multiple different composition.
U.S. Pat. No. 4,374,029 issued on Feb. 15, 1983, to Rajan A. Jaisinghani describes a regenerative filter for removing oil from a ship's bilge water. The filter bed consists of a 6 in. layer of anthracite coal particles (0.75-0.85 mm.) over a 4 in. layer of silica sand grains (0.40-0.55 mm.) over a 20 in. layer of garnet sand (0.25-0.35 mm.). The filter bed is supported further by a five-layer bed starting from the top consisting of a first coarse rock layer (1 in. depth), first granite particle layer, a silica sand layer, a second granite particle layer, and a second coarse rock layer (3.5 in. depth). The filter is regenerated by backwashing with water, air, and water steps. The filter bed is distinguishable for its numerous layers for removing fuel oil from bilge water rather than the three-layer U-shaped filter of the present invention for filtering potable water.
U.S. Pat. No. 5,320,750 issued on Jun. 14, 1994, to Milos Krofts describes a two-stage water clarifier with a first filtrate isolation and improved backwashing and improved bubble generation. An inner cylindrical tank serves as a first stage flotation tank. The outer annular cylindrical tank serves as a second stage filtration tank with baffles in an upper region over a filter bed consisting of a sand layer (0.35 mm. diameter) under an anthracite layer (0.8-1.0 mm. diameter) with each layer 30 cm. in depth. The flotation water containing the sludge is filtered to supply backwashing water with compressed air. The two-stage water clarifier is distinguishable for the difference in structure and the use of only two layers of filter media.
Japan Patent Application No. 1-315388 published on Dec. 12, 1989, for Nittetsu Mining KK describes a sand filter for removing phosphorus from waste water comprising a ground cristobalite (0.5-3 mm.) layer below an anthracite layer and optionally above a zeolite layer to remove phosphoric acid values. The filter is distinguishable for its requirement for cristobalite which is quartz heated to 1200.degree. C.
Russia Patent Application No. 1662626 published on Jul. 15, 1991, for Lvov Railway describes an effluent water contact clarifier tank using several layers of filtering grain with different grain sizes and with different layer heights. Seven gravel layers increasing in size from 10-20 mm. to 0.3-0.7 from the bottom are utilized with the bottom layer surrounding an apertured distribution pipe. The influent liquid traverses the filter bed from the bottom to an overflow region on top. The apparatus is distinguishable for utilizing seven gravel layers.
None of the above inventions and patents, taken either singularly or in combination, is seen to describe the instant invention as claimed. Thus, a water filtration system solving the aforementioned problems is desired.